Phillips screw security bit?

D

David Farber

Guest
I'm trying to disassemble a Kill-A-Watt P4460. A device that was plugged
into it had some electrical problem and caused the circuit breaker in my
house to trip. When I removed the Kill-A-Watt from the ac outlet, the ground
pin had a nice burn mark on it and now the display is dead. There are three
Phillips screws on the back of the unit but one of them appears to have one
of those raised points in the center of it which prevent you from putting in
a regular bit. I cannot find any security tool in my collection that fits
this type of screw. I'm not even sure what to search for online. The screw
looks like a torx bit but it only has four notches. Any idea what tool fits
this?

Thanks for your reply.
--
David Farber
Los Osos, CA
 
The Kill-A-Watt appears to be a heavily integrated product. You probably
won't be able to fix it.

Various dealers often have it on sale. It might be less trouble to wait a
week or two.
 
William Sommerwerck wrote:
The Kill-A-Watt appears to be a heavily integrated product. You
probably won't be able to fix it.

Various dealers often have it on sale. It might be less trouble to
wait a week or two.
Click to expand...
No fusible link?

Thanks for your reply,

--
David Farber
Los Osos, CA
 
On Mon, 18 Oct 2010 12:09:59 -0700, "David Farber"
<farberbear.unspam@aol.com> wrote:

I'm trying to disassemble a Kill-A-Watt P4460. A device that was plugged
into it had some electrical problem and caused the circuit breaker in my
house to trip. When I removed the Kill-A-Watt from the ac outlet, the ground
pin had a nice burn mark on it and now the display is dead. There are three
Phillips screws on the back of the unit but one of them appears to have one
of those raised points in the center of it which prevent you from putting in
a regular bit. I cannot find any security tool in my collection that fits
this type of screw. I'm not even sure what to search for online. The screw
looks like a torx bit but it only has four notches. Any idea what tool fits
this?
Click to expand...
Hmmm. Just checked the back of the 4460 here and all three screw heads
are Philips. It's a few years old, though, so maybe their lawyers got
involved or something.

Regardless, I wonder if a "spanner security bit" would work here? It's
shaped rather like a regular flat-bladed screwdriver but with a notch in
the center. You could probably make one by sizing a small flatblade with
one of the other screws and grinding a notch in the center.

--
Rich Webb Norfolk, VA
 
"David Farber" <farberbear.unspam@aol.com> wrote in message
news:i9i7fk$j3r$1@news.eternal-september.org...
William Sommerwerck wrote:
The Kill-A-Watt appears to be a heavily integrated product. You
probably won't be able to fix it.

Various dealers often have it on sale. It might be less trouble to
wait a week or two.

No fusible link?

Thanks for your reply,
Click to expand...
Yeah, the whole thing is the fusible link.

tm
 
tm wrote:
"David Farber" <farberbear.unspam@aol.com> wrote in message
news:i9i7fk$j3r$1@news.eternal-september.org...
William Sommerwerck wrote:
The Kill-A-Watt appears to be a heavily integrated product. You
probably won't be able to fix it.

Various dealers often have it on sale. It might be less trouble to
wait a week or two.

No fusible link?

Thanks for your reply,


Yeah, the whole thing is the fusible link.

tm
Click to expand...
Nice. (-;

Thanks for you reply (I think)
--
David Farber
Los Osos, CA
 
"David Farber" <farberbear.unspam@aol.com> wrote in message
news:i9i84b$ncd$1@news.eternal-september.org...
tm wrote:
"David Farber" <farberbear.unspam@aol.com> wrote in message
news:i9i7fk$j3r$1@news.eternal-september.org...
William Sommerwerck wrote:
The Kill-A-Watt appears to be a heavily integrated product. You
probably won't be able to fix it.

Various dealers often have it on sale. It might be less trouble to
wait a week or two.

No fusible link?

Thanks for your reply,


Yeah, the whole thing is the fusible link.

tm

Nice. (-;

Thanks for you reply (I think)
--
Click to expand...
Well, there is a shunt about 1 mm in diameter in the L1 leg. N goes
straight through. There is a small fuse, a 0.47 uF cap, and a 100 ohm 1 watt
flame proof resistor supplying power to the active electronics. My unit is
several years old and has three phillips screws.

Is yours open from source to load?



tm
 
Rich Webb wrote:
On Mon, 18 Oct 2010 12:09:59 -0700, "David Farber"
farberbear.unspam@aol.com> wrote:

I'm trying to disassemble a Kill-A-Watt P4460. A device that was
plugged into it had some electrical problem and caused the circuit
breaker in my house to trip. When I removed the Kill-A-Watt from the
ac outlet, the ground pin had a nice burn mark on it and now the
display is dead. There are three Phillips screws on the back of the
unit but one of them appears to have one of those raised points in
the center of it which prevent you from putting in a regular bit. I
cannot find any security tool in my collection that fits this type
of screw. I'm not even sure what to search for online. The screw
looks like a torx bit but it only has four notches. Any idea what
tool fits this?

Hmmm. Just checked the back of the 4460 here and all three screw heads
are Philips. It's a few years old, though, so maybe their lawyers got
involved or something.

Regardless, I wonder if a "spanner security bit" would work here? It's
shaped rather like a regular flat-bladed screwdriver but with a notch
in the center. You could probably make one by sizing a small
flatblade with one of the other screws and grinding a notch in the
center.
Click to expand...
I took a very small regular flat-bladed screwdriver and didn't expect much.
However it was able to catch hold and remove the screw. The screw is just a
regular Phillips head that looks like it suffered some irregularities from
trying to be removed with the wrong tool. I guess it doesn't really matter
now. Inside, everything looks clean. There is a small 10mm pigtail 200ma
fuse which is in tact.

So I reassembled everything, plugged it back in and it worked. Now for the
big d'oh moment. I think when I tested the Kill-A-Watt after the blowout, it
was before I noticed the circuit breaker had been tripped. Ok, move along,
nothing to see here. (-:

Thanks for your reply.
--
David Farber
Los Osos, CA
 
tm wrote:
"David Farber" <farberbear.unspam@aol.com> wrote in message
news:i9i84b$ncd$1@news.eternal-september.org...
tm wrote:
"David Farber" <farberbear.unspam@aol.com> wrote in message
news:i9i7fk$j3r$1@news.eternal-september.org...
William Sommerwerck wrote:
The Kill-A-Watt appears to be a heavily integrated product. You
probably won't be able to fix it.

Various dealers often have it on sale. It might be less trouble to
wait a week or two.

No fusible link?

Thanks for your reply,


Yeah, the whole thing is the fusible link.

tm

Nice. (-;

Thanks for you reply (I think)
--

Well, there is a shunt about 1 mm in diameter in the L1 leg. N goes
straight through. There is a small fuse, a 0.47 uF cap, and a 100 ohm
1 watt flame proof resistor supplying power to the active
electronics. My unit is several years old and has three phillips
screws.
Is yours open from source to load?



tm
Click to expand...
Nothing open. The unit now works. Thanks for taking the trouble to research
this. See my post after Rich Webb's to see what happened.

--
David Farber
Los Osos, CA
 
On Mon, 18 Oct 2010 12:09:59 -0700, "David Farber"
<farberbear.unspam@aol.com> wrote:

The screw
looks like a torx bit but it only has four notches. Any idea what tool fits
this?
Click to expand...
To the best of my knowledge, there's no such thing. All my
Kill-a-watt boxes use standard Philips screw heads.

Photo of the guts which may help once you gain entry:
<http://802.11junk.com/jeffl/pics/drivel/slides/kill-a-watt.html>
The upper photo is the older 4 button version. The lower photo is the
5 button version. Except for the price tag, the differences are
subtle.

The fuse is labeled F1 in the lower left. I had the brass power plug
connections develop a broken solder connection, probably from
excessive movement of the power plug (i.e. tripping over the cord).

The patent might help if you have to troubleshoot down to the
component level:
<http://www.google.com/patents?id=G3MDAAAAEBAJ&dq=6095850>

Some litigatory entertainment value:
<http://greenpatentblog.com/2008/12/24/smartlabs-enjoined-parties-smart-management-focuses-issues-in-energy-meter-litigation/>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
 
Jeff Liebermann wrote:
On Mon, 18 Oct 2010 12:09:59 -0700, "David Farber"
farberbear.unspam@aol.com> wrote:

The screw
looks like a torx bit but it only has four notches. Any idea what
tool fits this?

To the best of my knowledge, there's no such thing. All my
Kill-a-watt boxes use standard Philips screw heads.

Photo of the guts which may help once you gain entry:
http://802.11junk.com/jeffl/pics/drivel/slides/kill-a-watt.html
The upper photo is the older 4 button version. The lower photo is the
5 button version. Except for the price tag, the differences are
subtle.

The fuse is labeled F1 in the lower left. I had the brass power plug
connections develop a broken solder connection, probably from
excessive movement of the power plug (i.e. tripping over the cord).

The patent might help if you have to troubleshoot down to the
component level:
http://www.google.com/patents?id=G3MDAAAAEBAJ&dq=6095850

Some litigatory entertainment value:
http://greenpatentblog.com/2008/12/24/smartlabs-enjoined-parties-smart-management-focuses-issues-in-energy-meter-litigation/
Click to expand...
Hi Jeff,

I posted a few minutes before your post that there was nothing wrong with
the meter. I had tested the meter before I had realized the circuit breaker
had tripped. The fact that the burn-marked ground terminal that plugs into
the wall did not connect to any of the circuitry in the Kill-A-Watt should
have been my first clue. It just passes the ground connection to the device
under test.

Thanks for your reply.
--
David Farber
Los Osos, CA
 
"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in
news:i9i6vm$4dl$1@news.eternal-september.org:

The Kill-A-Watt appears to be a heavily integrated product. You probably
won't be able to fix it.

Various dealers often have it on sale. It might be less trouble to wait a
week or two.
Click to expand...
it's still nice to be able to open one up and see what's inside.

--
Jim Yanik
jyanik
at
localnet
dot com
 
David Farber wrote:
Rich Webb wrote:
On Mon, 18 Oct 2010 12:09:59 -0700, "David Farber"
farberbear.unspam@aol.com> wrote:

I'm trying to disassemble a Kill-A-Watt P4460. A device that was
plugged into it had some electrical problem and caused the circuit
breaker in my house to trip. When I removed the Kill-A-Watt from the
ac outlet, the ground pin had a nice burn mark on it and now the
display is dead. There are three Phillips screws on the back of the
unit but one of them appears to have one of those raised points in
the center of it which prevent you from putting in a regular bit. I
cannot find any security tool in my collection that fits this type
of screw. I'm not even sure what to search for online. The screw
looks like a torx bit but it only has four notches. Any idea what
tool fits this?

Hmmm. Just checked the back of the 4460 here and all three screw heads
are Philips. It's a few years old, though, so maybe their lawyers got
involved or something.

Regardless, I wonder if a "spanner security bit" would work here? It's
shaped rather like a regular flat-bladed screwdriver but with a notch
in the center. You could probably make one by sizing a small
flatblade with one of the other screws and grinding a notch in the
center.

I took a very small regular flat-bladed screwdriver and didn't expect much.
However it was able to catch hold and remove the screw. The screw is just a
regular Phillips head that looks like it suffered some irregularities from
trying to be removed with the wrong tool. I guess it doesn't really matter
now. Inside, everything looks clean. There is a small 10mm pigtail 200ma
fuse which is in tact.

So I reassembled everything, plugged it back in and it worked. Now for the
big d'oh moment. I think when I tested the Kill-A-Watt after the blowout, it
was before I noticed the circuit breaker had been tripped. Ok, move along,
nothing to see here. (-:
Click to expand...

That calls for 30 wacks with a rubber chicken! ;-)


--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.
 
In article <i9icf7$oef$1@news.eternal-september.org>,
"David Farber" <farberbear.unspam@aol.com> wrote:

There is a small 10mm pigtail 200ma
fuse which is in tact.
Click to expand...
David-

I had a generator with a bad governor, putting out over 300 Volts. It
blew the 200 Ma fuse in my Kill-A-Watt.

I haven't been able to find a 200 Ma fuse. It turns out that a standard
1/4 inch 1/4 Amp fuse with wire leads soldered on, fits in the space
available. Its better than no fuse at all!

Your philips screw may have just had a mutilated standard head. But if
someone went into it before you, they could have replaced the screw with
one with a "Pozi-Drive" head that looks like philips from a distance.
The pozi-drive system can apply more torque to the screw than philips.

If you work on Hewlett Packard test equipment, it might be worthwhile
finding some pozi-drive bits.

Fred
 
You didn't mnetion what a Kill-A-Watt P4460 is in your original post.
For the benefit of others, I did a search online. It's an electricit
power meter to display how much energy you are using.

The maximum power of an appliance plugged should not exceed 1875 VA.

What did you have plugged in and how much power does it require?

The Torx bit with a hole in the centre is commonly found in moder
security bit sets. You should be able to find one in your loca
hardware store/supermarket. Otherwise, you'll find one on Ebay.

M. Joshi

David Farber;2517895 Wrote:
I'm trying to disassemble a Kill-A-Watt P4460. A device that was plugge

into it had some electrical problem and caused the circuit breaker in m

house to trip. When I removed the Kill-A-Watt from the ac outlet, th
ground
pin had a nice burn mark on it and now the display is dead. There ar
three
Phillips screws on the back of the unit but one of them appears to hav
one
of those raised points in the center of it which prevent you fro
putting in
a regular bit. I cannot find any security tool in my collection tha
fits
this type of screw. I'm not even sure what to search for online. Th
screw
looks like a torx bit but it only has four notches. Any idea what too
fits
this?

Thanks for your reply.
--
David Farber
Los Osos, C
Click to expand...

--
M.Joshi
 
No fusible link?
Click to expand...
My intuition is that the Kill-A-Watt doesn't have a fusible link. Its
sensing circuit is probably designed to handle 20A or so. The circuitry is
probably fed from a high-impedance resistive divider, which would not lend
itself to "fuse" protection.
 
It's still nice to be able to open one up and see what's inside.
Click to expand...
Of course! That's always fun. I've been tempted to open mine.
 
So I reassembled everything, plugged it back in and it worked.
Now for the big d'oh moment. I think when I tested the Kill-A-Watt
after the blowout, it was before I noticed the circuit breaker had
been tripped. Ok, move along, nothing to see here. (-:
Click to expand...
This raises a possibly related problem -- something I call "CMOS lockup". A
device starts working oddly, or not at all, and then after it's for a while,
it works again. I've seen this on at least four items.
 
On Mon, 18 Oct 2010 16:27:47 -0700, "William Sommerwerck"
<grizzledgeezer@comcast.net> wrote:

It's still nice to be able to open one up and see what's inside.

Of course! That's always fun. I've been tempted to open mine.
Click to expand...
A picture is worth well maybe a dozen words:
<http://802.11junk.com/jeffl/pics/drivel/slides/kill-a-watt.html>
The upper is the older 4 button variety. The lower version is 5
button. Also note the fuse in the lower left.

Max current is 15A (1875VA):
<http://www.p3international.com/products/special/P4400/P4400-CE.html>
<http://www.p3international.com/products/p4460.html>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
 
On Mon, 18 Oct 2010 13:59:13 -0700, "David Farber"
<farberbear.unspam@aol.com> wrote:

I took a very small regular flat-bladed screwdriver and didn't expect much.
However it was able to catch hold and remove the screw. The screw is just a
regular Phillips head that looks like it suffered some irregularities from
trying to be removed with the wrong tool. I guess it doesn't really matter
now. Inside, everything looks clean. There is a small 10mm pigtail 200ma
fuse which is in tact.

So I reassembled everything, plugged it back in and it worked. Now for the
big d'oh moment. I think when I tested the Kill-A-Watt after the blowout, it
was before I noticed the circuit breaker had been tripped. Ok, move along,
nothing to see here. (-:
Click to expand...
Got it. So, in addition to the rule "When all else fails, use a bigger
hammer," we should append "or a smaller screwdriver!"

Well, at least you had a good excuse to crack one open and take a look
at the works. No day is wasted when one has learned something new (or at
least took something new apart).

--
Rich Webb Norfolk, VA
 
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